The Usefulness of Intraoperative Cerebral C-Arm CT Angiogram for Implantation of Intracranial Depth Electrodes in Stereotactic Electroencephalography Procedure

BACKGROUND

Stereotactic electroencephalography (SEEG) is an invasive diagnostic tool for localizing the epileptic zone in patients with medically refractory focal epilepsy. Despite technical and imaging advances in guiding the electrode placement, vascular injury is still one of its most serious complications.

OBJECT

To investigate the usefulness of intraoperative cerebral C-arm CT angiogram (CCTA) in avoiding intracranial hemorrhagic complications during SEEG electrode implantation.

METHODS

Trajectory data from 12 patients who underwent SEEG electrode implantation were studied in detail. This included an analysis of the implantation of 146 SEEG electrodes, which were guided by intraoperative CCTA, as well as the standard planning based on preoperative contrast-enhanced MRI. In addition, a prospective analysis of SEEG hemorrhagic complications using the studied methodology was performed in a total of 87 patients receiving 1,310 electrodes.

RESULTS

There was no complication related to the CCTA itself. Intraoperative CCTA entailed modification of the original trajectory based on the preoperative MRI in 27 of 146 electrode implantations (18.5%). In 10 of them, a severe vascular complication was adverted by intraoperative CCTA. The safety of this new approach was also confirmed by the analysis of postinterventional CT, which revealed a symptomatic hematoma caused by 1 single electrode out of the 1,310 implanted.

CONCLUSIONS

This study showed that intraoperative CCTA in addition to preoperative MRI is useful in guiding a safer SEEG electrode implantation. The combination of both imaging modalities essentially minimizes the risk of serious hemorrhagic complications.

Subdural Hematoma and Oral Anticoagulation: A Therapeutic Dilemma from the Neurosurgical Point of View

BACKGROUND

Oral anticoagulation is a common prophylactic therapy for several diseases with a high thromboembolic risk. Such medication harbors a possible hemorrhage risk, with a special risk for subdural hematoma (SDH). The safety and efficacy of resumption of oral anticoagulation versus long-term discontinuation has not been fully clarified in patients who experienced SDH while under treatment with oral anticoagulation.

MATERIAL AND METHODS

We investigated the outcome of 49 patients who were identified retrospectively to have a SDH while receiving oral anticoagulation.

RESULTS

Most bleeding occurred while patients were within the recommended therapeutic window for oral anticoagulation. Mortality was 15%. The event-free survival probability was higher in the group of patients with reinstitution of phenprocoumon therapy than in the group without. Over a median follow-up of 32 months, thromboembolic events occurred in 4 of 23 patients without oral anticoagulation versus in none of 15 patients with phenprocoumon; hemorrhagic complications occurred in 1 in 23 versus 3 in 15 patients.

CONCLUSIONS

Reinstitution of oral anticoagulation with phenprocoumon after previous SDH appears to have an acceptable risk for hemorrhagic complications. Decision making might consider case-by-case differences. To establish specific guidelines, prospective large cohort studies are needed.

Subacute steroid-induced paraparesis: surgical treatment of a devastating "invisible" side effect

PURPOSE

To emphasize an underestimated side effect following long-term use of steroids.

METHODS

We report on surgical treatment of two patients with serious neurologic deficits caused by epidural spinal lipoma following long-term intake of cortisone.

RESULTS

Early decompression of the spinal cord by removal of epidural lipoma was the most effective treatment in these patients with progressive symptoms.

CONCLUSION

Diagnostic work-up of such patients should include early spinal MRI resulting in surgical intervention, if indicated. Decompression of the spinal cord eventually combined with fusion is necessary.

Histopathological features of the brain, liver, kidney and spleen following an innovative polytrauma model of the mouse

OBJECT

Among the various introduced experimental traumatic brain injury models, there is a clear paucity of proper experimental polytrauma models. To overcome this experimental gap we introduced such a polytrauma model in the mouse including traumatic brain injury. Here, we report on the histopathological features of the brain, lung, kidney, spleen and liver.

MATERIALS AND METHODS

20 male C57BL mice with a mean weight of 23 g were anesthetized with ketamine and xylazine. The anaesthetized animals were subjected to a controlled cortical impact (CCI) over the left parieto-temporal cortex using rounded-tip impounder for application of a standardized brain injury. Following fracture of the right femur using a guillotine, a volume-controlled hemorrhagic shock was induced. The control groups included animals with CCI only (n=20) and animals with femur fracture plus hemorrhagic shock without CCI (n=20). Subjects were sacrified at 96 h following trauma. Brain, lung, kidney, spleen and liver of the animals underwent histopathological examinations.

RESULTS

The mortality rate at 96 h was 25% in the polytrauma group versus 10% in the control groups. Within the histopathological investigations, polytraumatized animals differ from those with a single trauma (traumatic brain injury or femur fracture with hemorrhagic shock) with various severity.

CONCLUSION

The findings of this study show that such a polytrauma model can be standardized resulting in a reproducible damage. This model fulfills the requirements of a standardized animal model. It allows adequate analogies and inferences to the clinical situation of a polytrauma in humans.

The Adjustable proGAV Shunt

OBJECTIVE

To evaluate the reliability of the gravitation-assisted adjustable proGAV shunt system with a prospective multicenter study conducted in 10 German hospitals.

METHODS

Enrollment for this observational study began in April 2005 and concluded in February 2006. The protocol required re-examinations 3 and 6 months postoperatively and fixed the endpoint of follow-up at 12 months after implantation. Patients with different types of adult, juvenile, and pediatric hydrocephalus were included and 165 patients were enrolled; 9 died and 12 had incomplete follow-up.

RESULTS

Of the assessable 144 patients, 130 completed the protocol after 12 months, whereas 14 failed because of the need to explant the device, mainly because of infection. In 12 patients, components of the shunt, not the valve, were revised. In 65 of the 144 patients, there were 102 readjustments of the valve in 67 incidences because of underdrainage and in 35 because of overdrainage. In 1 case, readjustment was not possible. Determination of pressure level with the verification instrument was safe and corresponded to the required x-ray controls after adjustments. No unintended readjustments were noted.

CONCLUSION

The proGAV is a safe and reliable device.

Exophytic giant cell glioblastoma of the medulla oblongata

Giant cell glioblastoma is a rare variant within the spectrum of glioblastoma multiforme (GBM) tumors. A giant cell glioblastoma may be associated with a better prognosis than the common type of GBM after combined treatment involving tumor resection and radiochemotherapy. A giant cell glioblastoma may occur at various sites in the brain and spinal cord. To the authors' knowledge, this type of tumor has not been previously reported as arising as an exophytic tumor from the medulla oblongata. The authors report on a 40-year-old man who presented with a large tumor located in the caudal fourth ventricle. The tumor was removed completely and the patient underwent percutaneous radiotherapy with 60 Gy and concomitant chemotherapy with temozolomide. Histopathological examination of the tumor revealed the typical features of a giant cell glioblastoma. At the 2-year follow-up the patient was doing well and showed no signs of tumor recurrence. It is important to identify variants of GBM because they may predict favorable long-term outcome, even when they arise from the caudal brainstem.

Modified calcium accumulation after controlled cortical impact under cyclosporin A treatment: a 45Ca autoradiographic study

OBJECTIVE

As a neuroprotective drug, cyclosporin A (CsA) has been subject of multiple experimental works in traumatic brain injury (TBI) research. It is well known that CsA inhibits calcium (Ca2+) induced mitochondrial permeability transition (mPT). The aim of this study was to investigate the influence of CsA on the alteration of Ca2+ homeostasis after experimental brain injury.

METHODS

Sprague-Dawley male rats (n = 36) with a mean weight of 330 g (280-350 g) were general anesthetized with isofluran through gas mask. The anesthetized animals (n = 24) were subjected to a controlled cortical impact (CCI) over the left parietotemporal cortex using round-tip impounder with a 5 mm diameter at a velocity of approximately 3.7 m/s and a penetration depth of 2 mm. The sham group (n = 12) underwent anesthesia and craniotomy without CCI. In the CCI groups, CsA (n = 12) or vehicle (n = 12) was administered 15 minutes post-injury with a subsequent i.p. injection after 24 hours. Thirty-three hours after injury or sham craniotomy, 45calcium (45Ca) suspended in physiologic saline solution was injected in the left femoral vein. Five hours after isotope administration, animals were killed and the brain was quickly removed and placed in powdered dry ice. Coronal plane sections (20 microm thick) taken every 400 microm from the frontal cortex through the occipital cortex, were exposed to cyclotron films for 14 days at -18 degrees C. Relative optical density was utilized to provide a relative measure of 45Ca accumulation within seven different structures.

RESULTS

The difference of 45Ca accumulation (measured by relative optical density) in the CsA group was greater by 30-70% in the following structures compared to vehicle treated traumatized animals: temporal cortex, CA1, anteromedial and posteromedial thalamus (p < 0.05).

CONCLUSION

Post-traumatic 45Ca accumulation is modified under CsA. The crucial neuroprotective effect of CsA might be unrelated to a reduction of post-traumatic Ca2+ accumulation, especially with regard to the importance of Ca2+ as an intracellular messenger governing a large number of cellular functions.

Image-guided craniotomy for frontal sinus preservation during meningioma surgery

OBJECTIVE

Preservation of the frontal sinus (FS) during the frontolateral approach to the skull base reduces morbidity, enhances patient comfort, and speeds up the surgical procedure. Due to its irregular outline, mental reconstruction of the borders of FS from two-dimensional images is challenging during surgery. This study was designed to evaluate the impact of neuronavigation on identification and preservation of the FS during frontolateral craniotomies.

METHODS

Forty-five patients with pathologies located in the anterior skull base and in the parasellar region were included. A standard computed tomography (CT) sequence was obtained from each patient and uploaded onto an image-guidance system for volumetric rendering of 3D images. The outline of the FS was visualized and the distance between its lateral border and the mid-pupillary line (MPL) was measured. The results were used for navigated craniotomies and compared to the intra-operative findings.

RESULTS

The FS was located medial, on and lateral to the MPL in 32, 4 and 9 cases, respectively. The individual outline of the FS could be identified with a mean target registration error of 1.4mm (+/-0.7 mm). The craniotomy could be custom-tailored for each patient according to the individualized landmarks while visualizing the lesion and the surgical landmarks simultaneously. Unintended opening of the frontal sinus or orbit did not occur in any of these cases.

CONCLUSION

Image-guided craniotomies based on 3D volumetric image rendering allow for fast and reliable demarcation of complex anatomical structures hidden from direct view in frontolateral approaches. The outline of the frontal sinus and the orbit can be appraised at a glance providing additional safety and precision during craniotomy.

Chordomas of the skull base: surgical management and outcome

OBJECT

The goal of this study was to report on the surgical management of skull base chordomas and to evaluate both the short- and long-term treatment outcomes.

METHODS

The authors retrospectively studied data from 49 patients who had undergone consecutive surgeries at a single institution. They also analyzed patterns of chordoma extension. Complications and surgery-related morbidity were recorded. A Kaplan-Meier analysis was performed to determine survival rates in patients 5 and 10 years after their first surgery. Operative approaches were selected on the basis of the predominant tumor extension.

RESULTS

The approach used most frequently was the transethmoidal in 36.3%, followed by the pterional in 23.4% and the retrosigmoid in 23.4%. The tumor was totally removed in 49.4% and subtotally in 50.6%. The rate of total removal was highest at initial surgery (78%) and progressively declined thereafter. In 11.8% of cases a new neurological deficit developed, while the preoperative deficit remained unchanged. In 20% of cases the preoperative deficits improved, but new deficits also appeared. The 5- and 10-year survival rates are 65 and 39%, respectively.

CONCLUSIONS

With an individually tailored surgical approach, total tumor removal in 78% of the cases was achieved at the initial surgery. Radical surgery appears to increase slightly the surgical morbidity, but at the same time prolongs the recurrence-free interval. Chordomas cannot be regarded as surgically curable tumors given the 5- and 10-year survival rates in patients harboring such lesions.

Management of vestibular schwannomas in young patients-comparison of clinical features and outcome with adult patients

OBJECTS

Vestibular schwannomas (VS) in young patients are rare. They are regarded to have different biological characteristics. Our objective is to analyze a series of such patients, with respect to their clinical presentation, treatment, and outcome and to compare the results to a matched series of adult patients.

MATERIALS AND METHODS

Retrospective analysis of 20 patients under 21 years of age. All patients underwent surgery via the retrosigmoid approach. The analysis included: age, gender, tumor size, clinical, and neurological pre- and postoperative status including cochlear and facial nerve function, and complications. Statistical comparison of the young patient's data with a series of 200 adult patients previously published by the authors.

CONCLUSIONS

The current study demonstrates that the outcome after surgical management in patients harboring VS does not show any significant difference between young and adult patients.

Cavernous Hemangioma of the Cavernous Sinus, Skin, and Retina: Hemodynamic Changes after Treatment: Case Report

OBJECTIVE

There are several reports concerning cavernous hemangiomas of the skin and central nervous system. Additional retinal involvement has also been reported.

CLINICAL PRESENTATION

The authors report a 69-year-old woman with a giant extra-axial cavernous hemangioma of the right cavernous sinus involving the supra- and parasellar region, retina, and skin.

INTERVENTION

Shrinkage of its cutaneous part lead to subsequent increase of the volume of the intracranial part. Owing to compression of the optic and the oculomotor nerves, oculomotor disturbances, ptosis, and visual impairment to 0.2 occurred. Via a pterional approach microsurgical removal of the tumor except for a remnant of the intracavernous part was performed.

CONCLUSION

Hemodynamic connection between cutaneous, retinal, and intracranial hemangiomas should be considered.

RESPONSE OF C-REACTIVE PROTEIN AFTER CRANIOTOMY FOR MICROSURGERY OF INTRACRANIAL TUMORS

OBJECTIVE

C-reactive protein (CRP) is used as an indicator of inflammatory processes. However, its expression is unspecific and will increase after surgery. Without normative data on its regular course after craniotomy, postoperative infection can barely be detected or excluded.

METHODS

CRP was measured for 10 days in 46 patients who underwent elective craniotomy for microsurgery of intracranial tumors.

RESULTS

After craniotomy, CRP rapidly increased to reach a peak mean value of 32.43 ± 38.02 mg/l (P &lt; 0.001) on the second postoperative day. In 39 patients (85%), CRP reached its maximum level within the first 2 days. From Days 3 to 5 after surgery, mean CRP values constantly and significantly declined (P &lt; 0.001) to arrive at a mean of 6.67 ± 10.80 mg/l) on the fifth postoperative day. On Day 4, the mean CRP level returned to below one-third of the peak value (10.63 ± 17.08 mg/l). On an individual basis, this was true for 34 patients (74%). During the period of initial increase of CRP until the second postoperative day, there was no significant correlation between CRP and erythrocyte sedimentation rate, body temperature, hemoglobin, hematocrit, red cell count, platelet count, and white cell count. CRP increase was more pronounced with intrinsic brain tumors and was not correlated to the degree of malignancy.

CONCLUSION

Because CRP can be considerably increased in patients for 4 days after regular intracranial surgery, its diagnostic value during this period is limited. Only prolonged elevation or a secondary increase may indicate an ongoing infection.

Ventriculoperitoneal shunt dysfunction in a patient presenting with neurogenic pulmonary edema

✓ The authors report on a patient with dysfunction of a ventriculoperitoneal shunt who presented with two episodes of neurogenic pulmonary edema within the space of a few months. The edema resolved on correction of the shunt dysfunction. Because neurogenic pulmonary edema may be a rare consequence of shunt dysfunction, it is important to recognize this unusual association and provide appropriate diagnostic measures and treatment.

Prognostic parameters for flare in systemic lupus erythematosus

OBJECTIVE

To characterize prognostic parameters for systemic lupus erythematosus (SLE) flares.

METHODS

In a prospective study, 120 SLE patients attending our out-patient clinic were evaluated every 3 months for 2 yr. At every visit clinical manifestations and laboratory parameters were assessed and the SLE disease activity index (SLEDAI) was determined. A correlation analysis of the number of flares in the first year and SLEDAI as a marker of disease activity after 1 and 2 yr with several parameters determined at the start of the study was performed.

RESULTS

Flares were predicted by erythrocyte sedimentation rate (P=0.001), anaemia (P=0.006) and lymphopenia (P=0.005). The SLEDAI after 1 yr was predicted by the titre of antinuclear antibodies (P=0.009), antibodies against double-stranded DNA (P=0.007), lymphopenia (P=0.007), anaemia (P=0.0002) and SLEDAI determined at the start of the study (P=0.001).

CONCLUSIONS

Anaemia and lymphopenia predict both flares and SLEDAI within the next year of follow-up.